In mammals, the length and growth rate of nails is related to the length of the terminal phalanges (outermost finger bones). Thus, in humans, the nail of the index finger grows faster than that of the little finger; and fingernails grow up to four times faster than toenails.  Don't forget to check out our Kickstarter Campaign! If you love Curionic pledge what you can! Even a dollar and a share helps!